April 2023
Equine Infectious Diseases
Brett A. Sponseller, Editor
One constant in veterinary practice is “change,” and in the case of infectious diseases, not only is our understanding of potential pathogens improving—a positive change—but also many features of the pathogens are changing, perhaps posing new clinical challenges. Antimicrobial resistance is an increasingly concerning feature in managing bacterial diseases in horses of all ages, including Rhodococcus equi. Dr Sanz provides context for management options, including active surveillance, and reviews considerations in adjunct plasma administration. As for Clostridioides difficile, a contentious name change has been made, and the recent detection of “human isolates” in companion animals has raised the possibility of (reverse) zoonotic transmission of C difficile, emphasizing the need for a One Health approach in equine practice. Drs Kuttappan, Mooyottu, and Sponseller summarize disease associated with C difficile and review recent findings spanning several equine enteric clostridial diseases. Dr Burgess provides a complete synopsis of Salmonella from the standpoint of clinical disease, shedding, risk factors, mitigation approaches, and public health concerns, while Dr Taylor reviews the known causative agents of Potomac Horse Fever and treatment approaches, and Dr Kopper reviews rotaviral diarrhea, providing an update on a ruminant-like group B rotavirus outbreak that appeared in 2022 in central Kentucky. Another RNA virus, also prone to change, is the fodder of Dr Pusterla’s exposé and pertains to equine coronavirus; however, he provides a word of caution regarding SARS-2 and the potential for adaptation to the equine host. Drs Ruby and Janes review infectious causes of equine placentitis and abortion and provide helpful suggestions to optimize obtaining a diagnosis.
